🔗 Azure VNet Peering: Dashboard Steps

📌 Overview

VNet Peering connects two separate Virtual Networks (VNets) so they can talk to each other using private IP addresses. It’s like building a direct bridge between two isolated islands.

Effect: VMs in VNet-A can ping VMs in VNet-B.
Performance: High speed, low latency (traffic uses Microsoft's backbone).

Hinglish Analogy: "Do alag colonies (VNets) ke beech mein ek private bridge banana, taaki log (data) bina main road (Internet) par gaye ek dusre se mil sakein."

✅ Prerequisites

Before you start, ensure you have:

Two VNets (e.g., VNet-A and VNet-B).
No Overlapping Address Spaces (e.g., 10.0.0.0/16 and 10.1.0.0/16 is OK. 10.0.0.0/16 and 10.0.0.0/16 will FAIL).

🛠️ Step-by-Step: Creating a Peering

In the modern Azure Portal, you can create the link for BOTH sides in one go.

1. Go to the First VNet

Navigate to Virtual Networks.
Click on your first VNet (e.g., VNet-A).

2. Open Peering Menu

On the left sidebar, under Settings, click Peerings.
Click the + Add button at the top.

3. Configure "This Virtual Network" (VNet-A Side)

Peering Link Name: Give it a name (e.g., Link-to-B).
Traffic to Remote Virtual Network: Allow (Default).
Traffic Forwarded from Remote Virtual Network: Block (Unless you are doing specialized routing).
Virtual Network Gateway: Leave as None (unless setting up Gateway Transit).

4. Configure "Remote Virtual Network" (VNet-B Side)

Peering Link Name: Name the reverse link (e.g., Link-to-A).
Virtual Network: Select VNet-B from the dropdown list.
Traffic to Remote Virtual Network: Allow.

5. Finalize

Click Add.
Azure will validate and create TWO peering links (one in A, one in B).

🚦 Verifying the Connection

Wait for a few seconds.
Refresh the Peerings list.
Peering Status: Should show Connected.
- If it says Initiated, it means only one side is linked. Wait or check the other VNet.

⚙️ Key Settings Explained

Setting	Meaning	Use Case
Allow Traffic to Remote	Can I talk to them?	Always Yes for normal communication.
Allow Traffic Forwarded	Can I accept traffic not originating from them?	Use Yes if the other side is a specific Router/Gateway/NVA.
Use Remote Gateway	Can I use their VPN Gateway?	Use Yes in Hub-Spoke topology (Spoke uses Hub's VPN).

⚡ Exam Tips

Cost: Peering is NOT free. You pay for data ingress and egress across the peering.
Transitive: Peering is non-transitive.
- If A matches B, and B matches C... A cannot talk to C. (You need to peer A directly to C).
Cross-Region: You can peer VNets in different regions (Global VNet Peering).